Network Security

MAC Address Analyzer

Every vendor writes MAC addresses differently, and the first byte carries two flags that matter in network forensics: whether the frame is multicast, and whether the address was randomised by the device.

All parsing is arithmetic done in your browser. No vendor lookup service is contacted, so nothing you type leaves the device.

What the flags tell an analyst

  • Bit 0 of the first byte marks multicast traffic -- useful when triaging noisy broadcast domains.
  • Bit 1 marks a locally administered address; modern phones randomise Wi-Fi MACs, so device tracking by MAC is unreliable.
  • The first three bytes (OUI) identify the manufacturer and help spot rogue or unexpected hardware.
  • MAC addresses are trivially spoofed, so never use them as the only network access control.